Safety stop mechanism for straight bar knitting machine



Jan. 6, 1970 R. ANKEM 3,487,661

SAFETY STOP MECHANISM FOR STRAIGHT BAR KNITTING MACHINE Filed March 4,1968 2 Sheets-Sheet 1 Jan. 6, 1970 R. ANKE 3,487,66

SAFETY STOP MECHANISM FOR STRAIGHT BAR KNITTING MACHINE Filed March 4,1968 2 Sheets-Sheet 2 United States Patent 3,487,661 SAFETY STOPMECHANISM FOR STRAIGHT BAR KNITTING MACHINE Rudolph Anke, Reading, Pm,ass gnor, by mesne ass gnments, to North American Rockwell Corporation,Pittsburgh, Pa., a corporation of Delaware Filed Mar. 4, 1968, Ser. No.710,212

Int. Cl. DiMb 35/10 U.S. Cl. 66--157 7 Claims ABSTRACT OF THE DISCLOSURESafety stop means for a camshaft of a knitting machine, the safety stopmeans being operative to prevent rotation of the cam shaft in adirection reverse to the power operated direction thereof and beingoperative to permit reverse rotation of the camshaft during manualoperation thereof.

BACKGROUND OF THE INVENTION Field of the invention escription of theprior art Heretofore straight bar or full-fashioned knitting machineswere provided with a camshaft for operating the knitting elements of themachine, and means for driving the camshaft of the type disclosed in US.Patent No. 1,706,645, issued Mar. 26, 1929, the drive means including ahandwheel shaft extending along the front of the machine and driven by amotor, a drive shaft driven from the handwheel shaft and gearsconnecting the drive shaft to the camshaft. Associated with thehandwheel shaft was a brake or safety stop means of the type disclosedin US. PatentNo. 1,711,301, issued Apr. 30, 1929 which included manuallyoperated means for activating the safety stop means to prevent reverserotation of the shafts when the machine was conditioned for poweroperation and for inactivating the safety stop means to permit reverserotation of the shafts by manual rotation of the handwheel shaft in thereverse direction.

More recently, in order to eliminate the constantly rotating handwheelshaft and to reduce the manual power required to rotate the shafts inthe reverse direction when required the manual means was redesigned toinclude a jack shaft which was connected to and driven by the motor anddriving connections between the jack shaft and drive shaft. The drivemeans also included a manually operated handwheel shaft extending fromthe front to the back of the machine, a worm on the handwheel shaftmeshing with a worm wheel associated with the motor shaft, clutchmembers associated with the motor shaft and worm wheel and manuallyoperated means for inactivating the clutch members for power operationof the machine and for activating the clutch members for manualoperation of the machine by the handwheel shaft. The jack shaft wasprovided with safety stop means similar to that disclosed in said PatentNo. 1,711,301 and manually operated means for activating the safety stopmeans to prevent reverse operation of the motor and shafts when themachine was conditioned for power operation and for inactivating thesafety stop means to permit manual operation of the shafts in both thepower operated and reverse directions.

When the safety stop means was associated with the handwheel shaft atthe front of the machine and the stop means was inadvertently allowed toremain in active condition the operator was unable to exert sufficientforce to overcome the braking force of the safety stop means to rotatethe handwheel shaft in the reverse direction. However, when the safetystop means was associated with the manually operated worm and worm wheeland the safety stop means was inadvertently allowed to remain in activecondition, sufficient manual force could be exerted through the worm andworm wheel to reverse the rotation of the shafts and smash the safetystop means.

SUMMARY OF THE INVENTION Briefly summarized the invention resides in theprovision of safety stop means associated with the operating shafts of astraight bar knitting machine having both power means and manual meansfor operating the shafts. The manual operating means and safety stopmeans are controlled by common means to inactivate the manual operatingmeans and activate the safety stop means to prevent reverse rotation ofthe shafts when the machine is conditioned for power operation and toactivate the manual operating means and inactivate the safety stop meansto permit the shafts to be manually rotated in both the power operatedand reverse directions when the machine is conditioned for manualoperation.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-sectional view takentransversely through a full-fashioned knitting machine showing the drivemechanism of the machine with means according to the inventionincorporated therein;

FIG. 2 is a plan view on an enlarged scale of a portion of the mechanismof FIG. 1;

FIG. 3 is a view on an enlarged scale of a portion of FIG. 1; and

FIG. 4 is a cross-sectional view on an enlarged scale taken on the lineand in the direction of the arrows 44 of FIG. 3.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIG. 1 of thedrawings there is shown a portion of 9. preferably multi-sectionfull-fashioned knitting machine for knitting fabric blanks, such as forhosiery, sweaters and the like, the machine including a center frame 10,a back beam 11 and a front beam 12. The beams 11 and 12 and center andfront beds (not shown) are secured to the center frames and end frames(not shown) to form the usual framework of the machine. Mounted in thecenter and end frames is a camshaft 15 having cams for operating needlesand other elements required to form the fabric blanks and a drive shaft16 having a gear 17 meshing with a gear 20 on the camshaft. The driveshaft 16 is driven by a link belt 21 or the like from a short jack shaft22 rotatably supported in brackets, one of which is shown at 25 in FIGS.3 and 4, which are secured to the back beam 11, and the jack shaft is inturn driven by a link belt 26 from a shaft 27 of an electric motor 30carried on a base member 31 mounted in fixed position on the back beam11 and front beam 12. The camshaft 15 is rotated by motor 30 throughshafts 16 and 22 in a counterclockwise direction as indicated by thearrow in FIG. 1 and hereinafter referred to as the power operateddirection.

The camshaft 15 is also adapted to be manually rotated both in the poweroperated direction and in the direction reverse thereto. The means forthis purpose includes a shaft 32, which extends from the front to theback of the machine, from left to right as viewed in FIG. 1, the shaft32 being rotatably mounted in a bracket 35 carried on one of the centerframes and a bearing member 36 (FIG. 2). The bearing member 36 issecured by bolts 37 to a platelike bracket 40 which is in turnadjustably secured by bolts 41 to a bracket 42 mounted in fixed positionon the back beam 11 (FIGS. 2 and 3). A worm 45 fixed on the right end ofthe shaft 32 is in meshing engagement with a worm wheel 46 having a hubportion rotatably mounted in a bore in the bracket 40'. The worm wheelis fixed against axial movement in the bore by engagement of the wormwheel with one face of the bracket and engagement of a plate 50 securedto the hub portion with the other face of the bracket (FIG. 2).

Secured on the end of the shaft 27 of the motor 30 is a clutch disc 51having notches for receiving teeth of a clutch 52 mounted in an innerbore in the worm wheel 46. A key is fixed on the clutch sleeve forengagement in a keyway (not shown) in the inner bore of the worm wheelto cause the clutch sleeve to rotate with the worm wheel and permitaxial movement of the clutch sleeve and the teeth thereon into and outof engagement with the clutch disc 51. For axially moving the clutchsleeve in the worm wheel, the clutch sleeve is provided with an annulargroove 55 adapted to receive the ends of pins 56 carried in arms 57 of aforked end 58 of a lever 60 pivoted on a stud 61 carried in the bracket42. An arm 62 of the lever 60 is connected by a universal joint 65 toone end of a rod 66, the rod extending toward the front of the machinefrom the arm for engagement in a vertically extending slot 67 in abracket 70 secured to the front beam 12 (FIG. 1). A collar 71 on the rod66 is adapted to engage in back of a stop finger 72 on the bracket tohold the rod when it is moved toward the left to the position of FIG. 1to shift the clutch sleeve 52 into engagement with the clutch disc 51.The rod 66- is raised to disengage the collar 71 from the stop fingeragainst the bias of a spring 75 connected between the rod and bracket 70when the rod is to be moved toward the right from its position of FIG. 1to turn lever 60 clockwise from its position of FIG. 2 to shift theclutch sleeve out of engagement with the clutch disc.

When the machine is to be power operated by the motor 30 the rod 66 ismanually moved toward the right from its position of FIG. 1 to disengagethe clutch sleeve 52 from the clutch disc 51 on the motor shaft 27. Atthis time the clutch sleeve 52 engages and closes a normally open switch76 connected into the operating circuit of the motor to condition theoperating circuit to permit the motor to be started and stopped underthe control of pattern and manually operated means conventionallyprovided on the machine. Each time that the motor circuit is opened tostop the machine, during the period the machine is conditioned for poweroperation, the camshaft must be prevented from rotating in a directionreverse to its power operated direction in order to prevent damage toboth the fabric forming elements of the machine and the fabric formedthereby.

Mechanisms of the type described have heretofore been employed andprovide the environment for the instant invention which serves toprevent reverse rotation of the camshaft referred to above. In itspreferred embodiment the present invention comprises safety stop orbackstop means including an over-running roller clutch assembly 77 whichis mounted on a sleeve 80 secured to the end of the jack shaft 22, theclutch assembly being positioned on the sleeve between an enlarged headportion 81 of the sleeve and a collar 82 fixed on the shaft 22 (FIG. 4).The clutch assembly 77, which is of a commercial type such as shown inUs. Patent No. 3,241,641, has an outer shell adapted to be secured in abore 85, as by press fitting, in an outer sleeve 86. Mounted in thesleeve 86 and secured thereto for rotation therewith as by key 87 arefirst and second ratchets 9G and 91 of first and second means forcontrolling the operation of the clutch assembly 77. The teeth of theratchet which are directed in one direction, are adapted to be engagedby a first pawl 92 pivotally mounted on a pin 95 carried in the bracket25 to arrest the movement of the clutch assembly 77 to permit the shaft22 to rotate freely in one direction relative the clutch assembly. Theteeth of the ratchet 91, which are directed in a direction opposite tothe direction of the teeth of ratchet 90, are adapted to be engaged by asecond pawl 96 also pivotally mounted on the pin 95 to arrest themovement of the clutch assembly to cause the rollers of the clutchassembly to grip the sleeve and prevent rotation of the shaft 22 in theopposite direction. The pawls 92 and 96 are positioned in side-by-siderelationship on the pin 95 between a collar 97, secured to the pin by aset screw 100, and a shoulder 191 on the pin (FIG. 4) and the pawls arebiased toward engagement with their ratchets by springs 102 connectedbetween the pawls and a pin 105 in the bracket 25 (FIG. 3).

During operation of the machine by the motor the rod 66 is moved towardthe right from the position of FIG. 1 to disengage the clutch sleeve 52from the clutch disc 51 to inactivate the manually operated means and toclose the switch 76 to condition the motor circuit and motor for poweroperation as hereinbefore set forth. Also at this time the pawls 92 and96 are engaged with the teeth of the ratchets 90 and 91, respectively,to prevent rotation of the ratchets, outer sleeve 86 and the clutchassembly 77 with the shaft 22 as the latter is rotated by the motor inthe power operated direction. Engagement of the pawls with theirrespective ratchets 90 and 91 also causes the rollers of the clutchassembly 77 to grip the sleeve 80 and prevent reverse rotation of theshaft when the motor is stopped.

When the machine is to be manually operated, the rod 66 is moved to itsposition of FIG. 1 to shift the clutch sleeve 52 into engagement withthe clutch disc 51 and to disengage the clutch sleeve from the switch 76thereby permitting the latter to open and inactivate the motor operatingcircuit. The shaft 32 may then be rotated by a handwheel 106 secured toleft end of the shaft 32 to turn the motor shaft 27 to operate theshafts 15, 16 and 22 in the power operated direction. In order to alsopermit the shaft 32 to be turned to rotate the motor and shafts in thereverse direction, the pawl 96 must be disengaged from the ratchet 91.Thereafter, when the shaft 32 is turned to rotate the motor and shaftsin the reverse direction the rollers of the clutch assembly 77 are movedinto gripping engagement with the sleeve 86 to cause the sleeve andclutch assembly to rotate in the reverse direction with the shaft 22.

In order to disengage the pawl 96 from the ratchet 91 the pawl isprovided with an arm 107 for engagement with one arm 110 of a lever 111pivoted on a stud 112 carried by the bracket 74. The lever 111 has asecond arm 115 for engagement with a finger 116 secured to lever 60 byscrews 117 (FIG. 2). When therod 66 is moved to its position of FIG. 1to condition the machine for manual operation, the finger 116 moveslever 111 clock wise to disengage the pawl 96 from the ratchet 91 topermit the clutch assembly 77 to rotate with shaft 22 when the motor andshafts are rotated in the reverse direction by the shaft 32.

It is believed to be obvious from the foregoing that when the poweroperated means is activated and the manual operating means isinactivated, the safety stop means is conditioned to permit rotation ofthe camshaft by the power operated means in the power operated directionand to prevent rotation of the camshaft in the direction reverse to thepower operated direction. Furthermore, when the power operated means isinactivated and the manual means is activated, the safety stop means isconditioned to permit rotation of the camshaft by the manual operatedmeans in both the power operated and reverse directions.

Of course, the improvements specifically shown and described by whichthe above described results are obtained, can be changed and modified invarious ways without departing from the invention herein disclosed andhereinafter claimed.

I claim:

1. In a straight bar knitting machine having a camshaft, power means foroperating said camshaft in one direction to form fabric on Said machine,manual means for operating said camshaft, and a control member movablefrom a first position to activate said power means to operate saidcamshaft and to inactivate said manual means to a second position toinactivate said power means and activate said manual means to operatesaid camshaft, the improvement including safety stop means associatedwith said camshaft, a first means for controlling the operation of saidsafety stop means during the operation of said camshaft in said onedirection, a second means for controlling the operation of said safetystop means to control the operation of said camshaft in a directionreverse to said one direction, means for operating said secondcontrolling means in said first position of said control member tocondition said safety stop means to prevent operation of said camshaftin said reverse direction and means operated by said control member insaid second position to operate said second controlling means tocondition said safety stop means to permit operation of said camshaft insaid reverse direction.

2. In a straight bar knitting machine having a camshaft, power means foroperating said camshaft in one direction to form fabric on said machine,manual means for operating said camshaft, and a control member movablefrom a first position to activate said power means to operate saidcamshaft and to inactivate said manual means to a second position toinactivate said power means and activate said manual means to operatesaid camshaft, the improvement including safety stop means comprisingoverrunning clutch means associated with said camshaft, a first meansfor controlling the operation of said overrunning clutch means duringoperation of said camshaft in said one direction, and a second means forcontrolling the operation of said overrunning clutch means to controlthe operation of said camshaft in a direction reverse to said onedirection.

3. In a machine according to claim 2 in which said first controllingmeans includes first arresting means for preventing rotation of saidoverrunning clutch means in a first direction during rotation of saidcamshaft in said one direction, and said second controlling meansincludes second arresting means for preventing rotation of saidoverrunning clutch means in a second direction to cause said overrunningclutch means to prevent rotation of said camshaft in said reversedirection.

4. A machine according to claim 3 in which said first arresting meansincludes a first ratchet and a first pawl cooperating with said firstratchet, and said second arresting means includes a second ratchet and asecond pawl engageable with said second ratchet.

5. In a machine according to claim 4 in which there is means fordisengaging said second pawl from said second ratchet to permit saidoverrunning clutch means to rotate in said second direction and permitrotation of said camshaft in said reverse direction.

6. In a machine according to claim 5 in which there is means foroperating said disengaging means to disengage said second pawl from saidsecond ratchet.

7. In a machine according to claim 5 in which there is means operated bysaid control member in said second position for operating saiddisengaging means to disengage said second pawl from said secondratchet.

References Cited UNITED STATES PATENTS 1,813,163 7/1931 Howie.

1,939,505 12/1933 Lieberknecht.

2,178,591 1l/1939 Lieberknecht.

2,363,535 11/ 1944 Lambach 66-157 X 2,649,703 8/1953 Wickardt 66-82MERVIN STEIN, Primary Examiner US. Cl. X.R. 6682

